6 Most controversial moments in SummerSlam history

#5. Brock Lesnar and The Undertaker's controversial SummerSlam finish in 2015

Things were extremely personal when #TheBeast @BrockLesnar battled #ThePhenom #Undertaker at #SummerSlam 2015! Relive the FULL MATCH here ⬇️ @HeymanHustle #FBF https://t.co/kLfyWWr09Z pic.twitter.com/Vqs6A1czWK

— WWE India (@WWEIndia) October 18, 2019

The 2015 edition of SummerSlam was headlined by Brock Lesnar and The Undertaker. At Battleground 2015, Lesnar was on the verge of defeating Seth Rollins to reclaim the WWE World Heavyweight Championship.

However, the lights would go off and The Undertaker would return to set up a blockbuster SummerSlam clash against Brock Lesnar. It was well over a year after the streak had ended and Lesnar had been on a tear, minus his defeat at WrestleMania 31.

The return was big enough and a night later on RAW, authority figure Triple H was doing his best to book the main event of SummerSlam. The match itself was far better than their clash at WrestleMania 30, although that bout is remembered more for the outcome than the quality of the match itself.

I’ve been lucky enough to attend #SummerSlam five times from 2015-2019. In 2015, I got to see the excellent big fight main event with Undertaker & Brock Lesnar. After WMXXX being so disappointing, this match had a great build & is one of my favourite Lesnar matches of this run. pic.twitter.com/aWeKvHPdli

— Kenny McIntosh 🏳️‍🌈 (@KennyMcITR) August 21, 2020

At the pay-per-view, there was a moment in the finale where Brock Lesnar seemed to make The Undertaker tap out, but it wasn't in the referee's view. Although the time keeper called it, the match went on and The Phenom went on to make Lesnar pass out with the Hell's Gate - but not before getting flipped off by The Beast Incarnate.

All in all, the controversial finish to SummerSlam 2015 was meant to set up their final clash at Hell in a Cell a couple of months later. But it was nothing short of confusing.